Modest protection of early hydrocortisone treatment in a rat model of volume-controlled haemorrhage

Resuscitation after hemorrhagic shock: the effect on the liver--a review of experimental data

The liver is currently considered to be one of the first organs to be subjected to the hypoxic insult inflicted by hemorrhagic shock. The oxidative injury caused by resuscitation also targets the liver and can lead to malfunction and the eventual failure of this organ. Each of the various fluids, vasoactive drugs, and pharmacologic substances used for resuscitation has its own distinct effect(s) on the liver, and the anesthetic agents used during surgical resuscitation also have an impact on hepatocytes. The aim of our study was to identify the specific effect of these substances on the liver. To this end, we conducted a literature search of MEDLINE for all types of articles published in English, with a focus on articles published in the last 12 years. Our search terms were "hemorrhagic shock," "liver," "resuscitation," "vasopressors," and "anesthesia." Experimental studies form the majority of articles found in bibliographic databases. The effect of a specific resuscitation agent on the liver is assessed mainly by measuring apoptotic pathway regulators and inflammation-induced indicators. Apart from a wide range of pharmacological substances, modifications of Ringer's Lactate, colloids, and pyruvate provide protection to the liver after hemorrhage and resuscitation. In this setting, it is of paramount importance that the treating physician recognize those agents that may attenuate liver injury and avoid using those which inflict additional damage.

Insights into the role of interleukin-6 in the induction of hepatic injury after trauma-hemorrhagic shock

Although systemic interleukin-6 (IL-6) level is elevated, hepatocellular function is impaired and liver injury occurs after trauma-hemorrhage (T-H), it remains unknown whether a causal relationship exists between elevated IL-6 levels and liver injury after T-H. We hypothesized that IL-6 is causative in the development of hepatic dysfunction and injury after T-H. To examine this, adult male Sprague-Dawley rats underwent a 5-cm midline laparotomy and were subjected to hemorrhagic shock (blood pressure = 35 mmHg for ∼90 min), followed by resuscitation (Ringer lactate, 4 times the shed blood volume). At 2, 5, and 24 h thereafter, blood samples were collected and the liver isolated and perfused for 60 min. Portal inflow pressure was measured, and perfusate samples were collected to measure IL-6, alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels. A significant positive correlation between plasma levels of IL-6 and ALT and perfusate levels of IL-6 and LDH levels was observed. In a second series of experiments, rats were treated with immunoglobulin G (IgG) or antibodies against rat IL-6 (anti-IL-6) at the onset of resuscitation. At 5 h after resuscitation, anti-IL-6 treatment attenuated the T-H induced increases in plasma ALT and thromboxane B2 (a thromboxane A2 metabolite) levels, and bile flow was normalized to sham levels. Perfusion of livers from normal rats with IL-6 did not alter portal pressure; however, perfusion of a stable thromboxane A2 analog dose dependently increased portal pressure. Thus IL-6 plays a significant role in the induction of hepatic dysfunction and liver injury after T-H that appears to be in part mediated by increased thromboxane A2 levels.